The discovery of prebiotic molecules in interstellar space suggests some basic chemicals key to life may have formed between the stars, U.S. astronomers say.

Using the National Science Foundation's Green Bank Telescope in West Virginia to study a giant cloud of gas some 25,000 light-years from Earth, near the center of our Milky Way galaxy, scientists say they found evidence of a molecule thought to be a precursor to a key component of DNA and another that may have a role in the formation of the amino acid alanine.

"Finding these molecules in an interstellar gas cloud means that important building blocks for DNA and amino acids can 'seed' newly-formed planets with the chemical precursors for life," Anthony Remijan of the National Radio Astronomy Observatory said.

The newly discovered interstellar molecules, which may have formed on dusty ice grains floating between the stars, are intermediate stages in multistep chemical processes leading to biological molecules, the researcher said.

"We need to do further experiments to better understand how these reactions work, but it could be that some of the first key steps toward biological chemicals occurred on tiny ice grains," Remijan said.